an abc news exclusive. Our team embedded in afghanistan when word crossed that an afghan soldier, a trainee turned on the americans killing three and wounding several others. Muhammad lila in afghanistan where the injured troops are being treated. Reporter: I'm standing outside the hospital where the wounded americans were air lifted after today's attack. Me and my producer were a few minutes away on a routine patrol when everything changed. It started with attack helicopters circling the air. Down below as we patrol the village we got word over the radio. I'm tracking green on blue medevac. It happened during a meeting at this joint u.S. Afghan base. We were scheduled to be there but missed it by just a few minutes because our patrol was running late. If we had been on time, this would be a very different story. Earlier this afghan colonel at the base boasted his soldiers could defeat the taliban. An hour later two turned their weapons on the americans they were working alongside killing three and wounding three more. We scrambled to get back to the base but it was in lockdown. The wounded men and women air lifted here to the next closest base. While morale on this base might be low, as a sign of resolve tonight the american flag is still flying high. David, even though it's a difficult time on the base, without fail each and every soldier says that they are resolved to keep on fighting until this country is safe.

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